Research about eye health and eye health services in Pacific Island Countries and Territories: a scoping review

Summary Background We aimed to summarise the extent and nature of published research about eye health and eye health services in Pacific Island Countries and Territories since 1980. Methods We searched Medline, EMBASE, Global Health and Cochrane Library to identify publications about eye health and eye health services in 22 Pacific Island Countries and Territories from 1 January 1980 to 26 January 2024. Study selection and data extraction were conducted by two reviewers independently. Findings Of the 1610 publications identified, 180 were included. This research was most commonly conducted in Papua New Guinea (n = 52) or Fiji (n = 33) and focused on diabetic retinopathy (n = 29) or trachoma (n = 18), with few focused on cataract or refractive error. While eye health services research was common in the past, recent research focused on trachoma. The included research was largely undertaken and funded by people and organisations from Australia, Aotearoa New Zealand and the USA, though authors with Pacific affiliations is increasing. Interpretation Few countries have up-to-date estimates of the prevalence of vision impairment or service coverage to enable evidence-informed planning. Increased effort is required to strengthen research capability to ensure research priorities in eye health are set by Pacific Peoples. Funding The Fred Hollows Foundation New Zealand.

ii Publications conducted across more than one country What was the research about?
Twenty publica�ons (11%) included more than one Pacific Island Country, area, or territory.For these mul�country publica�ons, four reported popula�on-wide prevalence of specific condi�ons.The two most recent of these (both published in 2020) es�mated the prevalence of trachoma (one in Vanuatu and Kiriba�, and another across Solomon Islands and Vanuatu).The other two popula�on-based prevalence studies included an inves�ga�on of the prevalence of trachoma in 2009 (including Fiji, Kiriba�, Nauru, Solomon Islands, and Vanuatu) and a 1995 publica�on to understand the magnitude of vitamin A deficiency across five countries (Cook Islands, Kiriba�, Solomon Island and Vanuatu).There was also a notable publica�on conducted in Nauru and the Solomon Islands that compared complica�ons of diabetes before and a�er an interven�on.
Just under half of the mul�-country publica�ons did not to target a specific condi�on (n=9/20, 45%).These publica�ons were looking at the bigger picture of service provision in the region, many specifically targe�ng workforce training development.Even commentaries about more than one Pacific Island Country, area, or territory tended to focus on the reflec�ons on the eye care workforce.Mul�-country research appears to be a newer trend, with most publica�ons published since 2005.iii

Papua New Guinea
What was the research about?
There were 61 publications that included PNG, and 52 specifically about PNG.The focus of the PNG specific research has been on less commonly researched eye conditions (coded at 'Other condition' in the figure below).These conditions include tumours/growths (n=3), ocular trauma (n=3), ocular leprosy (n=2), and a host of rare conditions.Almost half of these publications were describing service-based outcomes (n=24, 46%), and 6 additional publications are case publications.There were five publications that aimed to assess prevalence in population-based samples.Of these, the most common focus was vision impairment and its causes.The research in PNG has shifted from a focus descriptions of patients accessing services for less common conditions towards more robust analysis of vision impairment and it's causes.Who is conducting the research?
For publications conducted only in PNG, 45 publications (87%) had at least one author affiliated with institutions in Pacific Island Countries, and 22 publications had no external author affiliations.Accordingly, the most common author affiliation was PNG.Most publica�ons did not report a funder, but when disclosed, the most frequent funder of this research has been Fred Hollows Foundation New Zealand.

Fiji
What was the research about?
There were 46 publications that included Fiji, and 33 specifically about Fiji.Among the 33 publications specifically about Fiji, the most commonly targeted eye condition has been diabetic retinopathy (n=11, 33%).
The most common publication type has been population-based prevalence publications (n=9, 27%).The focus of these prevalence studies has been varied, including trachoma (n=3), and diabetic retinopathy (n=2).
Most of the research about eye health and eye health services in Fiji has been published since 2005, several reporting on the Fiji Eye Health Study 2009.

Figure 5. Publication type (upper panel) and timeline (lower panel). Each publication is represented by a dot, including study ID. Colour represents the targeted eye condition, according to the legend. The dashed line is the publication year mean. VI, vision impairment
Who is conducting the research?
For publications conducted only in Fiji, 23 publications (70%) had at least one author affiliated with institutions in Pacific Island Countries, and the most common author affiliation has been Fiji.Although most publications did not report funding, the most frequently reported funders have been AusAID and the Fred Hollows Foundation New Zealand.

Vanuatu What was the research about?
There were 35 publications that included Vanuatu, and 20 specifically about Vanuatu.Among the 20 publications specifically about Vanuatu, the most commonly targeted eye condition has been refractive error (n=7, 37%), including school-based prevalence publications mostly done in the 1980s.There were two more recent publications that aimed to assess prevalence in wider population-based samples.These publications were about trachoma (in 2017) and general vision impairment (in 1992).vii

Solomon Islands
What was the research about?
There were 23 publications that included Solomon Islands, and nine specifically about Solomon Islands.These nine publications have been relatively recent, and dominated by trachoma research, including population-based prevalence publications, and other supporting work about molecular basis of trachoma and potential use of mass drug administration.viii

Federated states of Micronesia
What was the research about?
There were eight publications that included Federated states of Micronesia, and five specifically about Federated states of Micronesia.All of these publications were on less common conditions.Two publica�ons were about a rare form of complete colour blindness found in Pingelap, called achromatopsia.Both of these focused on the gene�c basis of the condi�on.There was an addi�onal publica�on seeking to understand the gene�c basis of Leber's congenital amaurosis (LCA).Micro-ophthalmia and vitamin A deficiency were also described for pa�ents accessing service-based ac�vi�es.

Figure 11. Publication type (upper panel) and timeline (lower panel). Each publication is represented by a dot, including study ID. Colour represents the targeted eye condition, according to the legend. The dashed line is the publication year mean. VI, vision impairment
Who is conducting the research?
For publications conducted only in Federated states of Micronesia, two publications (33%) had at least one authors affiliated with institutions in Pacific Island Countries.No single funder was acknowledged more than others.The most common country of author affilia�on was the USA, and the top funder the (NIH) and many of the smaller funding agencies suppor�ng this work are also based in the USA.Who is conducting the research?
For publica�ons conducted only in Marshall Islands, three publica�ons (50%) had at least one author affiliated with ins�tu�ons in Pacific Island Countries.The most common country of author affilia�on was the USA, followed by the Marshall Islands.The most frequent funder of this research has been the Government of the USA.x

Nauru
What was the research about?
There were 12 publications that included Nauru, and five specifically about Nauru.All publications conducted specifically in Nauru are population-based prevalence publications.Note that several of the publications performed different analyses on data from a single study.Early publications (in the 1980s) targeted diabetic retinopathy (n=4, 67%), whereas the recent publication focused on the prevalence of trachoma.

Figure 15. Publication type (upper panel) and timeline (lower panel). Each publication is represented by a dot, including study ID. Colour represents the targeted eye condition, according to the legend. The dashed line is the publication year mean. VI, vision impairment
Who is conducting the research?
For publications conducted only in Nauru, four publications (67%) had at least one author affiliated with institutions in Pacific Island Countries.The most common country of author affilia�on was Australia.The early diabe�c re�nopathy research was funded by the NIH and WHO, whereas the newer research on trachoma is funded by wide a network of funders associated with global trachoma ini�a�ves.xi

Samoa
What was the research about?
There were 14 publications that included Samoa, and six specifically about Samoa.The most common focus of these six publications in terms of eye condition has been diabetic retinopathy (n=3, 50%).The more recent work has been piloting screening services for diabetes and glaucoma and developing ways to monitor the impact of vision impairment in children.One 1995 publication aimed to assess the prevalence of diabetic retinopathy in a population-based sample.

VI, vision impairment
Who is conducting the research?
For publications conducted only in Samoa, four publications (67%) had at least one authors affiliated with institutions in Pacific Island Countries.The most common country of author affiliation was the USA.Only two publications reported funding, each from a variety of funders.xii

American Samoa
What was the research about?
There were six publications that included American Samoa, and five specifically about American Samoa.
Most of these five publica�ons describe specific outbreaks of conjunc�vi�s in the 1980s and 1990s (n=4, 80%), which we categorised as descrip�ons of services.There was one more recent (2011) publica�on about vision impairment and its causes.This study sampled from people atending outreach services in the island of Tu'a.
Although only measuring those who atended outreach programmes, the sample represented 50% of the island's eligible popula�on.

VI, vision impairment
Who is conducting the research?
Two publications (40%) had at least one author affiliated with institutions in Pacific Island Countries.The most common country of author affilia�on was the USA.No single funder was acknowledged more than others, but when reported, funding was from the USA.xiii

Guam
What was the research about?
There were six publications that included Guam, and five specifically about Guam.Among these five publica�ons, most publica�ons have been about a type of re�nopathy thought to be connected to a rare neurological condi�on found in Guam (amyotrophic lateral sclerosis and parkinsonism-demen�a complex 'ALS-PDC', n=4, 80%).Most of this work was done in the 1980s and 1990s.The 2015 publica�on was specifically exploring the connec�on between the re�nopathy and ALS-PDC.

VI, vision impairment
Who is conducting the research?
For publications conducted only in Guam, each had at least one author affiliated with institutions in Guam (an unincorporated territory of the USA).No single funder was acknowledged more than others, but the bulk of funding was from North America.xiv

Kiribati
What was the research about?
There were 15 publications that included Kiribati, and five specifically about Kiribati.Among the five publications, the most common focus in terms of eye condition has been vitamin A deficiency (n=2, 40%).
Popula�on-based prevalence publica�ons have been the most common publica�on type (n=2, 40%), one in the 1990's about vitamin A deficiency and two more recent publica�ons about trachoma.

Figure 1 .
Figure 1.Publication type (upper panel) and timeline (lower panel).Each publication is represented by a dot, including study ID.Colour represents the targeted eye condition, according to the legend.The dashed line is the publication year mean.VI, vision impairmentWho is conducting the research?This mul�-county work appears to be driven by ins�tu�ons outside Pacific Island Countries, most frequently authors affiliated with ins�tu�ons in Aotearoa, New Zealand.Only nine publica�ons (45%) had an author affiliated with ins�tu�ons in Pacific Island Countries (among which the Solomon Islands was the most frequent country of affilia�on).Most publica�ons did not report a funder, but when disclosed, the most frequent funders are the Fred Hollows Founda�on Australia and the United stated Agency for Interna�onal Development (USAID).

Figure 2 .
Figure 2. Country of author affiliation and disclosed funding sources.For each subplot, up to the top 10 are displayed (note that each study can have multiple affiliations and funding sources).

Figure 3 .
Figure 3. Publication type (upper panel) and timeline (lower panel).Each publication is represented by a dot, including study ID.Colour represents the targeted eye condition, according to the legend.The dashed line is the publication year mean.VI, vision impairment.

Figure 4 .
Figure 4. Country of author affiliation and disclosed funding sources.For each subplot, up to the top 10 are displayed (note that each study can have multiple affiliations and funding sources).

Figure 6 .
Figure 6.Country of author affiliation and disclosed funding sources.For each subplot, up to the top 10 are displayed (note that each study can have multiple affiliations and funding sources).

Figure 7 .
Figure 7. Publication type (upper panel) and timeline (lower panel).Each publication is represented by a dot, including study ID.Colour represents the targeted eye condition, according to the legend.The dashed line is the publication year mean.VI, vision impairmentWho is conducting the research?For publications conducted only in Vanuatu, nine publications (45%) had at least one author affiliated with institutions in Pacific Island Countries.USA and Vanuatu are the most common countries of author affiliation.Most publications do not mention specific funding.When reported, the most frequent funder of this research has been the government of New Zealand.

Figure 8 .
Figure 8. Country of author affiliation and disclosed funding sources.For each subplot, up to the top 10 are displayed (note that each study can have multiple affiliations and funding sources).

Figure 9 .
Figure 9. Publication type (upper panel) and timeline (lower panel).Each publication is represented by a dot, including study ID.Colour represents the targeted eye condition, according to the legend.The dashed line is the publication year mean.VI, vision impairmentWho is conducting the research?For publications conducted only in Solomon Islands, eight publications (89%) had at least one author affiliated with institutions in Pacific Island Countries (with Solomon Island being the most frequent country affiliation), but there were no publications where all the authors were affiliated with institutions in the Solomon Islands.The trachoma work listed many funders (often embedded), with much of the support coming from organizations based in the United Kingdon (UK).

Figure 10 .
Figure 10.Country of author affiliation and disclosed funding sources.For each subplot, up to the top 10 are displayed (note that each study can have multiple affiliations and funding sources).

Figure 12 .
Figure 12.Country of author affiliation and disclosed funding sources.For each subplot, up to the top 10 are displayed (note that each study can have multiple affiliations and funding sources).

Figure 13 .
Figure 13.Publication type (upper panel) and timeline (lower panel).Each publication is represented by a dot, including study ID.Colour represents the targeted eye condition, according to the legend.The dashed line is the publication year mean.VI, vision impairment.

Figure 14 .
Figure 14.Country of author affiliation and disclosed funding sources.For each subplot, up to the top 10 are displayed (note that each study can have multiple affiliations and funding sources).

Figure 16 .
Figure 16.Country of author affiliation and disclosed funding sources.For each subplot, up to the top 10 are displayed (note that each study can have multiple affiliations and funding sources).

Figure 17 .
Figure 17.Publication type (upper panel) and timeline (lower panel).Each publication is represented by a dot, including study ID.Colour represents the targeted eye condition, according to the legend.The dashed line is the publication year mean.VI, vision impairment

Figure 18 .
Figure 18.Country of author affiliation and disclosed funding sources.For each subplot, up to the top 10 are displayed (note that each study can have multiple affiliations and funding sources).

Figure 19 .
Figure 19.Publication type (upper panel) and timeline (lower panel).Each publication is represented by a dot, including study ID.Colour represents the targeted eye condition, according to the legend.The dashed line is the publication year mean.VI, vision impairment

Figure 20 .
Figure 20.Country of author affiliation and disclosed funding sources.For each subplot, up to the top 10 are displayed (note that each study can have multiple affiliations and funding sources).

Figure 21 .
Figure 21.Publication type (upper panel) and timeline (lower panel).Each publication is represented by a dot, including study ID.Colour represents the targeted eye condition, according to the legend.The dashed line is the publication year mean.VI, vision impairment

Figure 22 .
Figure 22.Country of author affiliation and disclosed funding sources.For each subplot, up to the top 10 are displayed (note that each study can have multiple affiliations and funding sources).

Figure 23 .
Figure 23.Publication type (upper panel) and timeline (lower panel).Each publication is represented by a dot, including study ID.Colour represents the targeted eye condition, according to the legend.The dashed line is the publication year mean.VI, vision impairmentWho is conducting the research?For publica�ons conducted only in Kiriba�, four publica�ons (80%) had at least one author affiliated with ins�tu�ons in Pacific Island Countries, with Kiriba� the most common.The most frequent funder of this research has been USAID.

Figure 24 .
Figure 24.Country of author affiliation and disclosed funding sources.For each subplot, up to the top 10 are displayed (note that each study can have multiple affiliations and funding sources).